Which tree is most often used to make paper? How is paper made? Types of paper products

People invented paper thousands of years ago to record their thoughts and important technical discoveries. The method of transmitting information using paper, the production of which is growing every year, always remains relevant.

What are they made from?

Even Small child knows that the raw material for paper production is wood. Almost any breed is suitable for this:

• Chestnut;
• Birch;
• Poplar;
• Eucalyptus;
• Pine.

Logs from the sawmill are brought to mills, where they are cut into small pieces and then made into chips. To make 50 A4 sheets, you need 1 kg of wood. To reduce deforestation, waste paper, that is, used paper, is used. Straw, rice, cotton, as well as rag waste and asbestos are suitable for the production of raw materials.

In addition to these raw materials, production requires a lot of water. Paper mills are often built on the banks of rivers and lakes. Natural sources used for water intake and timber rafting.

How to make

Stages of the paper making process:

1. The logs are cleared of bark and sawn into chips.
2. They are immersed in water in a ratio of 5 parts wood to 95 parts water. As a result, the chips swell and bleach.
3. The material is boiled in solutions of acids, oxides and other substances. This is necessary to obtain a uniform viscous composition without impurities. The quality, grade and color of the paper depend on this stage.
4. The resulting cellulose is filtered. In its pure form it is used only for expensive grades of paper. For ordinary sheets, special additives are added to the cellulose.
5. Additional substances are introduced into the composition of semi-finished products that affect appearance paper. Resin is added to obtain a glossy surface, glue to increase strength, and dyes to create shade. The paraffin emulsion makes the paper suitable for writing and printing images. For whitening, chalk and talc are added to the mixture. Interestingly, paper pulp made from hemp and rice is white and does not require additional bleaching.
6. The pulp enters the paper machine. First, the composition falls on a mesh mesh, where water flows out of it. The fibers are intertwined along the movement of the machine, which makes it possible to obtain a strong base. The paper pulp is sent to presses, where it is compacted and even more water comes out.
7. The paper passes through metal drums where it is dried. The final processing takes place on the rollers, the paper web is compressed, leveled, compacted and finally dried.
8. The paper rolls are sent to the next machine, which cuts them into sheets and packages them.

The finished packages are delivered to stores and end consumers. Paper making is a fast process; today it is carried out using mechanical and electronic machines and practically does not require human participation. This allows the product to be produced in large volumes.

How it was made in ancient times

People left the first inscriptions on rocks, cave walls, and clay tablets. Birch bark, papyrus and parchment are the ancient ancestors of paper. You could write on them, but they didn't last long.

The first production was organized in China around 105. Plants - moss, grass, bamboo - were used to make paper. The fibers were soaked in water and then boiled with ash and lime. These substances are needed to dissolve lignin, a polymer that gives plants strength.

The raw materials were crushed into small fibers, vegetable juices and starch were added, and paper sheets were cast. After the water had drained off, the sheets were dried with a press. Over time, the production secret spread to the Arab lands, from where it came to Europe. There they began to make paper from wood; the first experiments were carried out at the beginning of the 18th century.

How to check quality

To check the quality of paper, several characteristics are used:

• Thickness. It is important to save same thickness on the entire batch of goods.
• Porosity. The larger it is, the better the printing ink holds.
• Opacity. This important characteristic for books and office paper. Newspaper sheets are made more transparent to save money.
• Smoothness. This characteristic improves image quality due to better contact of paper sheets with printing forms.
• Strength. Important for high-speed printing, as well as for packaging materials.
• Abrasion resistance. Directly affects durability finished books, manuscripts, newspapers.
• Absorbency. Affects the rate of penetration of paints.

Types of paper products

Modern paper production involves the production of different types:

• Newspaper. Inexpensive to produce and quickly absorbs paint.
• Offset. The most common type, used for printing books, notebooks, and for office purposes.
• Coated. Characterized by high quality and increased whiteness. Used for printing expensive catalogs.
• Packaging. The main thing for her is resistance to external environment. It is made from pure wood, as it requires little cost.
• Monetary. The highest quality type, used for printing banknotes.
• Cardboard. High density paper.

In Russia, the production of paper from wood is well developed, since our country is rich in forests. New trees are constantly planted in place of felled trees, this renews the resources of enterprises. Every city has waste paper collection points that provide additional raw materials for paper factories. Now you know how paper is made and what a complex process it is.

The Chinese made it from soaked plant fibers. Paper came to Europe between 1000 and 1100 years. It turned out that it can be made from wood, rags and even... from old paper - waste paper. It turned out that the paper could be used twice!

How is paper made these days?

Paper is produced in paper mills.

The main raw material for paper production is wood pulp. Cellulose is obtained from forest species: mainly from spruce, pine and birch, but eucalyptus, poplar, chestnut and other trees are also used.

At the factory, machines strip the bark from them and crush them into chips.

The most economical way to obtain wood pulp is mechanical: at a wood processing plant, timber is crushed into crumbs, which are mixed with water. Paper made from such cellulose is fragile and is most often used in the production of, for example, newspapers.

paper more High Quality made from cellulose obtained chemically. This wood pulp is used to make paper for books, brochures and fashion magazines, as well as durable wrapping materials.

In this case, the chips are sorted by size on special sieves and sent for cooking. The wood is boiled in special machines to which acid is added.

Cleaned and boiled wood is filtered and washed to remove impurities.

Waste paper can be added to the processed paper pulp, but only after the ink has been removed. At this stage of production, the processed pulp, consisting of wood fibers and water, is called raw paper.

Then, a special processing machine changes the shape and structure of the paper fibers. To do this, additional substances are added to the paper raw material. For example, adhesives - their presence in writing paper repels moisture. Or resins - thanks to them, what is written on paper with water-based ink does not spread and is easily recognized by the human eye. Paper used for printing does not require the same sizing as writing paper, because printing inks are not water-based and do not bleed.

After this, the paper is dyed in a mixer, where dyes or pigments are added, for example, finely ground coating substances. Thus, kaolin additives make paper white and opaque.

The paper pulp, turned into pulp, enters the paper making machine.

First, the slurry is poured onto the mesh of the paper machine. This mesh is stretched over two shafts and rotates all the time, carrying the paper pulp forward. At the mesh section, the formation of the paper web, called sheet forming, begins. This occurs by removing water from the fibrous material. As the paper pulp moves through belt conveyor Some of the water contained in it flows out through the mesh holes, and the paper fibers begin to intertwine with each other, forming the so-called roll tape.

The raw paper strip passes through a series of rollers. Some rollers squeeze out the water, others, heated from the inside with steam, dry it, and others polish it.

At the end of the wire section, the still wet paper web is moved to a pressing section, which is also called “wet pressing”. There, the paper web is mechanically dehydrated and further compacted.

Finally, the smooth white tape comes out of the machine and is wound into a huge roll.

Then these rolls are sent to printing houses or cut into sheets.

So, moving from machine to machine, the wood turns into white and clean paper.

Did you know...

To make 1 ton of paper you need 5.6 m 3 of wood. If we consider that the average volume of one log (tree) is 0.33 m 3, then 17 trees are required to produce 1 ton of paper.

And from 1 ton of paper you can make about 30 thousand ordinary student notebooks.

Paper is used in many areas of human activity. This includes a variety of packaging, wallpaper, posters and calendars. But biggest role paper played a role in the development of books as a source of knowledge dissemination. We'll tell you everything about paper that any literate person should know. Let's get started.

In this article we will look at paper production and how paper is made modern production. But first, let's take a quick look at how paper was made in ancient times.

How paper was made in ancient times

Ancient people left their first inscriptions on rocks, animal bones, clay and wax tablets, and parchment. But all methods of recording information had disadvantages, due to their weight, dimensions or cost. Making paper was difficult.

The prototype of paper can be called papyrus, which was made by the ancient Egyptians for many centuries. They extracted the core of the papyrus plant, soaked it, and then laid one layer on top of the other so that they lay perpendicular.

Then this paper was kept under pressure, which made it possible to obtain a durable and fairly hard material.

Paper making

You probably already know that paper is usually made from wood. Therefore, let's look at how paper is made from wood.

Most often, cellulose is used to make paper, which is obtained from spruce, pine, birch, pine needles, chestnut, etc. wood.

In a paper mill, tree trunks are stripped of their bark, ground, and allowed to swell in water. At this stage the percentage of water is 95% and 5 percent wood pulp.

The task of this stage is to grind the wood into fibrils - small fibers. The wood is boiled for a certain time in special solutions, which consist of a solution of acids. They must not only grind the cod, but also bleach the wood pulp.

This operation largely determines what grade of paper we get. After grinding, you need to clean the mass from unnecessary impurities and add binders and fillers to it. For this purpose organic and inorganic substances, various oxides.

Their task is to bind the substance into a uniform mass, a viscous mass.

After this, on special production lines, the resulting mass is formed into a paper sheet. In particular, the mass is poured onto a mesh surface, where a paper web is formed.

Next, it is coated with a number of substances, depending on the type of paper. For example, to produce coated paper, it is coated on one or both sides with a pigment-adhesive solution, which will make the product smoother and whiter. This process consists of several steps to increase the adhesion strength of the paper web layer.

Also, sizing can be applied to the surface of the paper. This is a substance that increases the resistance of paper to liquids, including water, glue or paint.

Next, the paper passes through heavy cylinders (calenders), which increase the evenness and smoothness of the paper and the paper is dried. It must be said that the finished paper has a moisture content of about 7%. If it will be higher percentage humidity, the material will become less durable; if there is less moisture, the paper will be fragile.

Cardboard is made using a similar method, only it is thicker. Cardboard is paper that is heavier, 250 grams/m2.

The finished paper is wound into rolls in a paper-making machine and sent to the printing house. Their paper is wound into rolls and cut into separate sheets, and goes to the printing shop.

Paper quality

The quality of paper is controlled by many indicators. These include whiteness, thickness, weight, smoothness, sizing, tensile and compressive strength, and opacity. Let's look at some in more detail.

Paper thickness affects the thickness of the book block. In some types of printing (gravure), it is important that the difference in sheet thickness is not large.

Paper porosity. The more, the better the paint adheres to the print. But the print turns out less saturated.

Opacity. In most cases, the paper should be opaque, otherwise it will front side the image from the back will appear.

Smoothness. Smooth paper makes it possible to reproduce small image elements on it. In addition, the material with a smooth surface allows for good contact with printing form.

Paper strength. Particularly important for packaging paper. But it is also needed for other types, because it makes it possible to print on it with high-speed printing machines.

Surface abrasion resistance. Printing inks have good viscosity and can pluck fibers from the surface during the printing process. This negatively affects the speed of the process, because you have to clean the mold frequently.

Absorbency. The higher this indicator, the faster the paint is fixed on the print.

Surface sizing. Gives strength to the surface layer, which reduces the amount of dust during printing and is resistant to water and glue.

Types of paper

Depending on the purpose, the composition of the paper and the method of its manufacture may differ.

Packaging. This paper has low color or smoothness requirements, but must be durable and resistant to environmental conditions.

Offset. Has a wide range of applications. Very often used for printing books and making notebooks and forms. Must be resistant to moisture, since it is associated with the use of a moisturizing solution.

Newspaper. Newspapers are often printed on it. It has an increased ink absorption rate, which is convenient when you need to print on high-speed printing machines.

. Has increased smoothness and whiteness. Used for printing high quality publications with big amount images, catalogs, leaflets, etc.

Cardboard. This is paper heavier than 250 grams/m2. Used for making hard book covers and various cards.

Cellulose. Very high-quality paper, which is almost 100 percent cellulose, is used for the production of banknotes and securities.

What is paper made of?

deforestation

After felling, the tree trunks are transported by large tractors and rail to paper mills. Here the logs are cut into smaller pieces and fed into production lines where they are crushed into chips.

We looked at how paper is made from wood, and you saw how important it is to recycle waste paper and reuse it in production, as well as rags. In addition, it is important to plant a new one in place of a felled tree.

Paper production requires large quantity trees, so it is common in those countries that have large tracts of trees: Finland, Russia, Canada.
Now you know how paper is made.

P.S. How making paper video:

Paper is consumed by people in huge quantities. One hundred and fifty kilograms per person per year. Read the article about what and how paper is made from.

Historical information

Long ago, in 105 BC, Cai Lun, an imperial subject from China, made paper from mulberry tree. He made a mixture of his wood, hemp, rags, added wood ash and put it all on a sieve to dry. After which I polished the dried mass with a stone.

The result was paper made from wood, and the Chinese eunuch became the first author of its technology. The Chinese think so. But scientists have a different opinion. This is due to the fact that archaeologists often find paper scraps in China that date back to an earlier period.

Raw materials

Paper is made from wood pulp, other fibers of plant origin: cane, rice, straw, hemp, as well as from rag waste, waste paper and other materials. Wood is used to produce cellulose different breeds trees. Wood pulp can be produced in several ways.

The mechanical method is considered the most economical. At a wood processing plant, the wood is crushed into crumbs. It is mixed with water. Cellulose paper obtained in this way is fragile, and newspapers are made from it. High quality paper is made from cellulose, which is produced using a chemical process. To do this from wooden beam fine chips are cut. It is sorted by size. Then they are immersed in a solution with chemicals and boiled in a special machine. After this, it is filtered and washed, as a result of which excess impurities are removed. This produces paper raw material called wood pulp. It is used to produce paper for magazines, books, brochures, and high-strength wrapping materials.

DIY sawdust paper

Sawdust from pine or spruce is filled with water and boiled for exactly one day. Caustic soda is added to the water. If you don't have it, you can use baking soda. After cooking, the mixture is washed with water and squeezed out. Then the sawdust is again poured into a pan of water and put on fire. As soon as it boils, the pan is removed from the heat and its contents are crushed using a mixer. The result is a mushy mass of uniform consistency.

While the sawdust is boiling, a frame is made, placed on a pallet, and gauze is stretched over it. The mass is poured onto the prepared frame and distributed evenly over the entire surface. Excess water will drain into the pan. But to quickly remove moisture, it should be blotted with absorbent wipes. Then the frame is turned over and the sheet obtained from the mass is easily separated from it.

The sheet must be covered on both sides with paper or newspaper and placed between the boards, pressed on top with something heavy. He should lie under such pressure for about five minutes. After this, the sheet is carefully placed on foil and dried in the sun, in the oven, near the radiator.

Compound

Wood paper is made from wood pulp obtained using mechanical method production. Sometimes other materials are used as a basis. This paper can be made even at home. But it will be of low quality.

Nowadays, cellulose is produced chemically using technological processes. To obtain high quality paper, it must contain the following ingredients:

• The sizing is hydrophobic, which prevents ink from spreading on the paper. They don't show through reverse side leaf. Rosin glue is used as sizing.
• Resin, glue or starch. Thanks to these substances, wood paper becomes more durable and resistant to various influences on it.
• Kaolin, talc or chalk make paper less transparent and increase its density.

Types of wood

It can be hard and soft. The first type of wood is obtained from coniferous species trees: pine, fir, spruce, sequoia and hemlock. Softwood is obtained from broadleaf species: beech, maple, poplar, birch, oak. In regions with tropical climate- made of teak, ebony and mahogany.

Paper made from these types of wood is highly valued. But, unfortunately, they are growing slowly. They are being cut down more than they are being reproduced. Therefore in tropical forests trees valuable species gets smaller.

Paper production today

Real paper is considered to be that which is made from a mass, the individual fibers of which are obtained by soaking cellulose raw materials. The mass is first mixed with water and then scooped out with a mold over which a mesh is stretched. Excess water drains off, the mass dries out, and a sheet of paper is obtained. This is how Chinese citizen Cai Lun received his first piece of paper. During this time, although about two thousand years have passed, no significant changes have occurred.

Today, paper production is carried out in modern factories with huge workshops, on the equipment of which various operations are performed. After obtaining wood pulp, the fibers are given shape and structure, for which paper raw materials are mixed with adhesives and resins. The glue repels water from the paper, and the resin prevents the ink from bleeding. Paper made of wood, the photo of which is presented for review, does not require such processing for printing purposes, since printing ink does not spread.

The next step is coloring. To do this, the paper is placed in a mixer with pigments or dyes. The mushy mass then goes into a machine called a paper making machine. After all the processing stages in this machine, the mass becomes a paper roll tape, which passes through many rollers: one squeezes out the water, another dries the tape, the third polishes it.

At the next stage, the paper is sent to the wet pressing workshop. Here the fibers are degreased and further compacted. The result is dry paper made from wood. white, wound into huge rolls that go to the printing house. There they are cut according to the required sizes.